The Cognitive Benefits of Cataract Surgery

Some 20 million Americans age 40 and older harbor a cataract in at least one eye, according to the Centers for Disease Control and Prevention. It’s a leading cause of blindness, but recent research suggests it may also contribute to depression and even dementia.

An analysis published in Scientific Reports in 2020 examined outcomes for 116,629 Taiwanese patients who’d received a cataract diagnosis between 2001 and 2015. During an average follow-up period of 7.8 years, Tzu Chi University researchers found that those who had undergone surgery to remove their cataracts were 25 percent less likely to develop depression than their counterparts who had not had surgery.

In 2021, Cecilia Lee, MD, MS, and her University of Washington colleagues reviewed a long-term memory study involving 3,038 seniors with cataracts but no symptoms of dementia. Nearly 1,400 of them eventually underwent cataract surgery, and researchers found that this group’s risk of receiving a dementia diagnosis in the succeeding years was 29 percent lower than that of those who avoided the procedure. The results were reported in JAMA Internal Medicine.

Interestingly, the cognitive benefits did not accrue to those who underwent surgery to repair glaucoma. “People might say that those who are healthy enough to have surgery are healthier in general, and therefore less likely to develop dementia in any case,” Lee tells the New York Times. “But when we see no association in glaucoma surgery, that supports the idea that it isn’t just eye surgery, or being healthy enough to undergo surgery, but rather that the effect is specific to cataract surgery.”

The mechanics at work here remain mysterious, but the results of both studies suggest that cataract surgery may offer patients a clearer view to a better quality of life.

This article originally appeared as “Cataract Surgery: A New View” in the September 2022 issue of Experience Life.